Cigarette paper



Patented 2 2, 1953 -CIGARETTE PAPER Milton 0. 'Schur, Asheville, and Robert M. Levy,

Brevard, N. C.', assignors to Ecusta Paper 001'- poration, a corporation of Delaware No Drawing. Application March 7, 1952,

' Serial No. 275,461

8 Claims. (01. 131-15)- Our invention 'relates'to cigarette paper and more particularly to improving theashing properties of cigarette paper when burned as the wrapper on a cigarette.

. A desirable paper ash is one that has a minimum f carbonized or incompletely burned residue, has'a grayish-white color, adheres to the tobaccoash and thereby avoids dropping of ashes on the{ smokers clothing, but is nevertheless easily fi-ickable at thewillof the smoker.

In U. S. Patent No. 2,580,568, issued January 1, 1952, to Robinson E. Matthews and Ward D. Harrison, there is disclosed a cigarette paper having the above-mentioned desirable ashing properties, whichare obtained by incorporating in the paper approximately 0.1% to 1% of ammonium phosphate. An improvement in that connection is disclosed in our U. S. Patent No. 2,580,610, issued January 1, 1952, which comprises incorporating in the cigarette paper, in addition to the ammonium phosphate, a very minute amount of phosphoric acid.

We have now discovered fromfurther research in this field that even more permanent ashing properties can be obtained by a particular combination of chemical compounds, namely, diammonium phosphate, guanidine carbonate and tetra-sodium pyrophosphate.

In accordance with .the present invention, a composition of the above-mentioned chemicals is prepared in aqueoussolution and incorporated in the cigarette paper web running on the paper machine at a pointprior to the final drying rolls. A convenient form of application is by means of the conventional size press, located near the middle of the drying section of the paper machine, so that the aqueous composition will be imparted to the partially-or completely dried paper sheet. 3 p

A typical but non-limiting formula for the aqueous composition, applicable in the size press, is as follows:

The above formula is based upon th pick-up of approximately 1 lb. of the aqueous composition per pound of paper on a dry basis, and the resulting treated paper will contain approximately 0.5% diammonium phosphate, 0.5% guanidine carbonate, and 0.03% tetrasodium pyrophosphate. These proportionate amounts may be varied within the following approximate I limits: 7

' Per cent Diammonium Phosphate 0.1 to 1.0 Guanidine Carbonate 0.1 to 1.5 Tetrasodium- Pyrophosphate 0 to 0.1

The above-indicated ranges for the different components of the composition are adjusted beshould be avoided to maintain the desired nortween two' extremes, namely, a maximum or upper limit at which the composition will begin to fireproof the cigarettepaper, which, of course,

- been found satisfactory in actual operation. The

' specific proportions given in the above formula are advantageous in certain instances and have given excellent results.

We believethat in the above composition the diammonium phosphate is the component that provides the desired grayish-white, clinging properties in the cigarette paper ash, while the guanidine carbonate and the tetrasodium pyrophosphate are the stabilizing components of the composition which impart permanency to the desired burning properties over a substantial period of time and even under varying storage conditions. Although the preferred results are obtained from a combination of the above three components, worth-while improvements in the permanency of the ashing properties have been obtained by a combination ofv the diammonium phosphate and the guanidine carbonate. Incorporating the tetrasodium pyrophosphate further insures the stability of the burning, properties imparted to the cigarette paper treated with this composition.

An illustrative commercial procedure for using the present invention in the manufacture of cigarette paper is as follows:

'A sheet of cigarette paper was formed in the conventional manner from a furnish comprised of beaten flax pulp and calcium carbonate filler. At a point in the drier where the water content of the paper was about equal in weight to the dry wei ht of the fiber and the filler, the paper was run through a size press and impregnated with a solution prepared according to the above formula. A weight of solution about equal to the weight 01 the dry contents the paper was imparted to the paper, and the paper was then completely dried by passage over drying cylinders in the conventional manner.

The stabilizing chest 01' the guanidine carbonate and tetrasodium pyrophosphate when the paper is storedat high humidity is noteworthy in that when the paper thus treated is kept in an atmosphere 01' 80% relative humidity for a period of thirty days, cigarettes wrapped in this paper still retain their fine ashing characteristies.

The stabilizing eiiect oi the guanidine earbonate and tetrasodium pyrophoephate is 01 special significance when the cigarette paper is on the cigarette, because the cigarette tobacco is moist and that condition accentuates the usual instability of the ashing properties of the paper. Cigarettes rolled in the paper, prepared as above described, burned so as to leave fine, discontinuous flakes of paper ash, which closely adhered to the tobacco ash, and these cigarettes upon storage retained their fine ashing properties, when burned, to a much better extent than when the guanidine carbonate and tetrasodium pyrophosphate were not used.

Instead oi the diammonium phosphate above described, we may use monoammonium phosphate or triammonium phosphate or mixtures of the three.

The filler commonly usedin cigarette paper to regulate the porosity, and hence the rate at which it burns on the cigarette, is calcium carbonate. It is ordinarily added to the flax pulp furnish in an amount suiilcient to give a filler content 0! about 20%-25% in' the finished paper, and it constitutes the principal ash-forming constituent in the cigarette paper.

Various modifications and changes may be made in the foregoing process, materials and products, without departing from the spirit and scope of our invention as defined in the appended claims.

We claim:

1. A combustible cigarette paper containing cellulosic fibers, calcium carbonate filler, and impregnated throughout with approximately 0.1% to 1% diammonium phosphate, approximately 0.1% to 1.5% guanidine carbonate, and not more than about 0.1% tetrasodium pyrophosphate, based on the dry weight of the cigarette paper.

2. A combustible cigarette paper containing cellulosic fibers, calcium carbonate filler, and impregnated throughout with approximately 0.1% to 1% diammonium phosphate, and approximately 0.1% to 1.5%guanidine carbonate, based on the dry weight of the cigarette paper.

3. A combustible cigarette paper containing cellulosic fibers, calcium carbonate filler, and

throughout with approximately 0.1% to 1% diammonium phosphate, approximately 0.1% to 1.5% guanidine carbonate and not more than about 0.1% tetrasodium pyrqphosphate, based on the dry weight 01' the cigarette paper.

6. A combustible cigarette paper containing flax fibers, calcium carbonate filler, and impregnated throughout with approximately 0.1% to 1% diammonium phosphate, and approximately 0.1% to 1.5% guanidine carbonate, based on the dryeweight of the cigarette paper.

7. A combustible cigarette paper containing flaxrilbers, calcium carbonate filler, and impregnated throughout with approximately 0.5% diammonium phosphate, 0.5% guanidine carbonate, and 0.03% tetrasodium pyrophosphate, based on the dry weight oi the cigarette paper.

8. A combustible cigarette paper containing flax fibers, calcium carbonate filler, and impregnated throughout with approximately 0.1% to 1% of an ammonium phosphate selected from the group consisting oi diammonium phosphate, monoammonium phosphate and triammonium phosphate, approximately 0.1% to 1.5% guanidine carbonate, and not more than about 0.1% tetrasodium pyrophosphate, based on the dry weight or the paper.

MILTON O. SCHUR. ROBERT M. LEVY.

References Cited in the tile 01 this patent 638,434 Great Britain June '7, 1950 

1. A COMBUSTIBLE CIGARETTE PAPER CONTAINING CELLULOSIC FIBERS, CALCIUM CARBOBATE FILLER, AND IMPREGNATED THROUGHOUT WITH APPROXIMATELY 0.1% TO 1% DIAMMONIUM PHOSPHATE, APPROXIMATELY 0.1% TO 1.5% GUANIDINE CARBONATE, AND NOT MORE THAN ABOUT 0.1% TETRASODIUM PYROPHOSPHATE, BASED ON THE DRY WEIGHT OF THE CIGARETTE PAPER. 